Emergency

Search Results for: file system diff

Fixing MySQL with a comment in the config file

A customer called with an emergency issue: A server that normally runs many MySQL instances wouldn’t start them up. Not only would it not start all of them, it wouldn’t even start the first one. …

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Different flavors of InnoDB flushing

In my recent benchmarks, such as this one about the Virident TachIon card, I used different values for innodb_buffer_pool_size, like 13GB, 52GB, and 144GB, for testing the tpcc-mysql database with size 100G. This was needed …

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Analyzing the distribution of InnoDB log file writes

I recently did a quick analysis of the distribution of writes to InnoDB’s log files. On a high-traffic commodity MySQL server running Percona XtraDB for a gaming workload (mostly inserts to the “moves” table), I …

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How innodb_open_files affects performance

Recently I looked at table_cache sizing which showed larger table cache does not always provides the best performance. So I decided to look at yet another similar variable – innodb_open_files which defines how many files …

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MySQL File System Fragmentation Benchmarks

Few days ago I wrote about testing writing to many files and seeing how this affects sequential read performance. I was very interested to see how it shows itself with real tables so I’ve got …

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Working with many files and file system fragmentation

Working on performance optimization project (not directly MySQL related) we did a test – creating 100 files writing 4K in the random file for some time and when checking the read speed on the files …

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Evaluating IO subsystem performance for MySQL Needs

I’m often asked how one can evaluate IO subsystem (Hard drive RAID or SAN) performance for MySQL needs so I’ve decided to write some simple steps you can take to get a good feeling about …

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RAID System performance surprises

Implementing MySQL database in 24/7 environments we typically hope for uniform component performance, or at least would like to be able to control it. Typically this is indeed the case, for example CPU will perform …

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Content delivery system design mistakes

This week I helped dealing with performance problems (part MySQL related and part related to LAMP in general) of system which does quite a bit of content delivery, serving file downloads and images – something …

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Percona Toolkit 2.2.15 is now available

Percona is pleased to announce the availability of Percona Toolkit 2.2.15.  Released August 28, 2015. Percona Toolkit is a collection of advanced command-line tools to perform a variety of MySQL server and system tasks that are too difficult or …

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